Electrically conductive support surface and related methods

ABSTRACT

Apparatus and methods for electrically grounding a support surface includes an at least partially perforated, electrically-conductive cover configured to extend at least partially across the top of the support surface and be electrically grounded to the earth.

This application is a continuation application of and claims priority toU.S. patent application Ser. No. 15/673,676 filed on Aug. 10, 2017entitled “Electrically Groundable Support Surface & Related Methods”,which is a continuation application of and claims priority to U.S.patent application Ser. No. 15/178,254 filed on Jun. 9, 2016, entitled“Apparatus and Methods for Electrically Grounding at Least One Mat in aLoad-Supporting Surface” and which issued as U.S. Pat. No. 9,735,510,which is a continuation-in-part application of and claims priority toU.S. patent application Ser. No. 14/838,064 filed on Aug. 27, 2015,entitled “Apparatus and Methods for Electrically Grounding aLoad-Supporting Surface” and which issued as U.S. Pat. No. 9,368,918 onJun. 14, 2016, which is a continuation application of and claimspriority to U.S. patent application Ser. No. 14/496,105 filed on Sep.25, 2014, entitled “Apparatus and Methods for Electrically Grounding aLoad-Supporting Surface” and which issued as U.S. Pat. No. 9,337,586 onMay 10, 2016, which claims priority to U.S. Provisional PatentApplication Ser. No. 61/888,580 filed on Oct. 9, 2013 and entitled“Apparatus and Methods for Electrically Grounding a Load-SupportingSurface”, all of which are hereby incorporated by reference herein intheir entireties.

FIELD OF THE DISCLOSURE

The present disclosure relates to load-supporting surface technologyand, more particularly, to apparatus and methods for forming anelectrically conductive and groundable support surface.

BACKGROUND

Temporary or semi-permanent support surfaces have been used forroadways, remote jobsites, industrial staging areas and the like in anever-increasing myriad of industries, such as the construction,military, oilfield, transportation, disaster response, utilities andentertainment industries. These support surfaces are often made up ofheavy duty mats, which are reusable and sometimes interlock together toform the support surface. In some instances, it is necessary ordesirable to provide apparatus and methods for electrically grounding atleast a portion of the support surface.

For example, it may be necessary or desirable to use a temporary orsemi-permanent electrically grounded support surface as part of anequipotential zone (EPZ). The EPZ is an arrangement typically designedso that dangerous electric potential differences do not appear acrossthe body of a person working on or near ground-based machinery. An EPZis often used during projects that involve working in close proximity toan energized power line. For example, in performing overhead power line(OHL) projects, the EPZ may prevent the installation crew from beingsubject to an electric shock caused by, for example, a circuit flashfrom the energized line to the conductors being worked on. In the EPZ,the equipment and personnel are typically on a work surface that iselectrically conductive and should be grounded to provide a natural pathfor large electrical voltages to flow.

Presently know solutions for temporary, or semi-permanent, electricallygrounded support surfaces include the use of aluminum access platesbolted together at each corner. These plates are believed to have one ormore disadvantages. For example, the plates may not overlap one anotherand therefore require a flat underlying surface. Otherwise, the edges ofthe plate(s) may protrude above the underlying surface and form a triphazard. For another example, the aluminum plates may have considerablescrap value and thus require 24-hour security to prevent theft. Forstill a further example, these plates may not be useful or adapted tootherwise serve as support surfaces when electrical grounding is notrequired or needed.

It should be understood that the above-described features, capabilitiesand disadvantages are provided for illustrative purposes only and arenot intended to limit the scope or subject matter of the appended claimsor those of any related patent application or patent. Thus, none of theappended claims or claims of any related application or patent should belimited by the above discussion or construed to address, include orexclude each or any of the above-cited features, capabilities ordisadvantages merely because of the mention thereof herein.

Accordingly, there exists a need for improved apparatus, systems andmethods useful in connection with providing an electrically conductiveand groundable support surface having one or more of the attributes orcapabilities described or shown in, or as may be apparent from, thevarious portions of this patent application.

BRIEF SUMMARY OF THE DISCLOSURE

Various embodiments of the present disclosure involve apparatus forelectrically grounding a portable mat and electrically connecting themat to at least one other electrically-conductive component. The matincludes a top and a bottom and is configured to be deployed on or nearthe surface of the earth. The apparatus includes a cover constructed atleast partially of electrically-conductive material. The cover isconfigured to be attached to the mat sufficient to prevent the coverfrom separating from the mat during use thereof. The cover includesmetallic, liquid permeable grating configured to extend at leastpartially across the top of the mat and be electrically grounded to theearth. At least one electrically-conductive interface is configured tofacilitate electrical connection of the cover to at least one otherelectrically-conductive component.

Certain embodiments of the present disclosure involve an electricallygroundable support surface for use on or near the earth's surface andbeing electrically connectable to at least one other support surface.The electrically groundable support surface includes a lower portionconfigured to be deployed on or near the surface of the earth, an atleast partially perforated liquid permeable cover portion constructed atleast partially of electrically-conductive material, associated with thelower portion and configured to extend at least partially across the topof the lower portion and be electrically grounded to the earth and atleast one electrically-conductive interface configured to electricallycouple the support surface to at least one other support surface.

In many embodiments, an apparatus for electrically grounding a portablemat having top and bottom surfaces and being constructed ofnon-conductive material is provided. The mat is configured to bedeployed on or near the surface of the earth and support the weight ofpersonnel, vehicles and equipment thereupon. The apparatus includes acover constructed at least partially of electrically-conductive materialand configured to support the weight of personnel, vehicles andequipment thereupon. The cover is engageable with the mat sufficient toprevent the cover from separating from the mat during use thereof andbeing selectively disengageable therefrom. The cover includes at leastone inner panel configured to extend at least partially across the topsurface of the mat and be electrically grounded to the earth.

The present disclosure includes embodiments involving an electricallygroundable support surface for use on or near the earth's surface andbeing electrically connectable to at least one otherelectrically-conductive component. The support surface includes a lowerportion having top and bottom surfaces and configured to be deployed onor near the surface of the earth. An electrically-conductive coverportion is constructed at least partially of perforated,electrically-conductive material, extends at least partially across thetop surface of the lower portion and is electrically groundable to theearth. The cover portion allows the passage of liquid through the coverportion and into contact with the lower portion. At least oneelectrically-conductive interface is configured to facilitate electricalconnection of the support surface to another electrically-conductivecomponent.

In the present disclosure, there are embodiments of an electricallygroundable, reusable, load-supporting surface adapted to be deployed onor near the surface of the earth. The load-supporting surface includes aplurality of lower portions and a plurality of electrically-conductivecover portions. At least one cover portion is associated with eachrespective lower portion, each cover portion including metallic gratingconstructed at least partially of electrically-conductive metal stripsforming openings therebetween. The metallic grating is configured toextend at least partially across the top face of the correspondingassociated lower portion. The respective electrically-conductive coverportions of different respective lower portions are configured to beelectrically interconnected and grounded to the earth to electricallyground the load-supporting surface.

In various embodiments, the present disclosure involves a method ofelectrically grounding a ground cover deployed on or near the surface ofthe earth in an equipotential zone to assist in preventing dangerouselectric potential differences from appearing across the body of aperson located on the ground cover. The ground cover includes a top anda bottom and is configured to support the weight of personnel, vehiclesand equipment thereupon. The method includes positioning a reusable,electrically-conductive cover at least partially across the top of theground cover so that an electrically-conductive metallic grating panelof the cover extends at least partially across the top of the groundcover. The electrically-conductive cover captures electrical current inthe equipotential zone. The electrically-conductive cover is grounded tothe earth to assist in preventing dangerous electric potentialdifferences from appearing across the body of a person located on theground cover.

In many embodiments, the present disclosure involves a method ofassembling and electrically grounding a load-supporting surfaceconfigured to be deployed on or near the surface of the earth. Themethod includes attaching an electrically-conductive cover portion atleast partially across the top surface of a lower portion. The coverportion, which includes a perforated, liquid permeable,electrically-conductive panel having metal strips and openings formedtherebetween, extends at least partially across the top surface of thelower portion and is configured to support the weight of personnelthereupon. The load-supporting surface is grounded to the earth.

In many embodiments, an apparatus for electrically grounding a portablemat having top and bottom surfaces and being constructed ofnon-conductive material is provided. The mat is configured to bedeployed on or near the surface of the earth and support the weight ofpersonnel, vehicles and equipment thereupon. The apparatus includes acover constructed at least partially of electrically-conductive materialand configured to support the weight of personnel, vehicles andequipment thereupon. The cover is engageable with the mat sufficient toprevent the cover from separating from the mat during use thereof andbeing selectively disengageable therefrom. The cover includes at leastone inner panel configured to extend at least partially across the topsurface of the mat and be electrically grounded to the earth.

There are embodiments involving an electrically groundable supportsurface for use on or near the earth's surface and being electricallyconnectable to at least one other support surface includes. A mat hastop and bottom surfaces and is configured to be deployed on or near thesurface of the earth and support the weight of personnel, vehicles andequipment thereupon. A reusable cover is constructed at least partiallyof electrically-conductive material and configured to support the weightof personnel, vehicles and equipment thereupon. The cover is associatedwith the mat, and configured to extend at least partially across the topsurface of the mat and be electrically grounded to the earth. The coverincludes at least one electrically-conductive interface configured to beelectrically coupled to another support surface.

The present disclosure includes embodiments of an electricallygroundable support surface for use on or near the earth's surface andbeing electrically connectable to at least one otherelectrically-conductive component. A mat includes top and bottomsurfaces and is configured to be deployed on or near the surface of theearth. An electrically-conductive cover is constructed at leastpartially of electrically-conductive material. Theelectrically-conductive cover is associated with the mat and has atleast one inner panel configured to extend at least partially across thetop surface of the mat and be electrically grounded to the earth. Atleast one electrically-conductive interface is configured to facilitateelectrical connection of the electrically-conductive cover to anotherelectrically-conductive component.

In many embodiments, an electrically groundable, reusable,load-supporting surface adapted to be deployed on or near the surface ofthe earth includes a plurality of mats. Each mat has respective top andbottom faces and is capable of supporting the weight of personnel,vehicles and equipment thereupon. A plurality of removable,electrically-conductive covers is included, at least one of which isassociated with each respective mat. Each removable cover includes atleast one inner panel constructed at least partially ofelectrically-conductive material. Each cover is configured to extend atleast partially across the top face of the corresponding associated matand support the weight of personnel, vehicles and equipment thereupon.The respective electrically-conductive covers of different respectivethe mats in the load-supporting surface are configured to beelectrically interconnected and grounded to the earth to electricallyground the load-supporting surface.

In various embodiments, a support surface for use on or near the earth'ssurface and being electrically groundable includes a reusable matconstructed of non-conductive material and having top and bottomsurfaces. The reusable mat is configured to be deployed on or near thesurface of the earth and support the weight of personnel, vehicles andequipment thereupon. At least one electrically-conductive cover isconstructed at least partially of electrically-conductive material andconfigured to support the weight of personnel, vehicles and equipmentthereupon. The cover is associated with the reusable mat and configuredto extend at least partially across the top surface of the mat and beelectrically grounded to the earth. The cover includes at least oneelectrically-conductive interface configured to serve as an electricalcoupling point to the support surface.

In many embodiments, a method of electrically grounding a planar,load-supporting mat deployed on or near the surface of the earthincludes positioning a reusable, electrically-conductive cover at leastpartially across the top surface of the mat so that anelectrically-conductive frame of the cover sits at or proximate to theperimeter of the top surface of the mat and an electrically-conductiveinner panel coupled to the frame and fitting at least partially withinthe frame extends at least partially across the top surface of the mat.The cover is releasably coupled to the mat and grounded to the earth.

There are embodiments involving a method of electrically connecting andgrounding at least two planar mats arranged in a reusable,load-supporting surface deployed on or near the surface of the earth.The method includes positioning at least one among a plurality ofelectrically-conductive covers at least partially across the top surfaceof each mat. Each cover is coupled to its associated mat. At least oneconductive interface of each cover is electrically coupled to anelectrically conductive interface of another cover. At least one coveris grounded to the earth.

In some embodiments, the present disclosure involves a system forelectrically grounding a reusable load-supporting surface deployed on ornear the surface of the earth. The system includes at least two mats atleast partially forming the load-supporting surface. Each mat hassubstantially planar respective top and bottom faces, multiple sides andat least one edge extending around each side. The mats are configured tosupport the weight and movement of personnel, vehicles and equipmentthereupon. A plurality of substantially planar, removable,electrically-conductive covers are constructed at least partially ofelectrically-conductive material and constructed and arranged to supportthe weight and movement of personnel, vehicles and equipment thereupon.Each cover extends at least partially across the top face of one of themats without extending over any of the edges thereof and is flexiblycoupled to the mat to allow the mat to flex, expand and contractrelative to the cover due to one or more environmental factors and themovement of personnel, vehicles and/or equipment across theload-supporting surface during normal, typical or expected useconditions without decoupling the cover from the mat or undesirablydamaging or deforming the cover or mat, while allowing the cover and matto support the weight and movement of personnel, vehicles and equipmentthereupon. Each cover includes at least one conductive interfaceconfigured to electrically couple the cover to another cover in theload-supporting surface. At least one of the covers is configured to beelectrically coupled to the earth.

In many embodiments, the present disclosure involves apparatus forelectrically grounding at least two mats of a load-supporting surfacedeployed on or near the surface of the earth. Each mat includessubstantially planar respective top and bottom faces, multiple sides andat least one edge extending around each side thereof. The mats areconstructed and arranged to support the weight and movement ofpersonnel, vehicles and equipment thereupon. The apparatus includes aplurality of substantially planar, removable, electrically-conductivecovers constructed at least partially of electrically-conductivematerial and constructed and arranged to support the weight and movementof personnel, vehicles and equipment thereupon. Each cover extends atleast partially across the top face of one of the mats without extendingover any of the edges thereof. Each cover includes at least oneconductive interface configured to electrically couple the cover toanother cover in the load-supporting surface. At least one of the coversis configured to be electrically coupled to the earth. A plurality ofadjustable, releasable couplers is configured to releasably couple eachcover to its associated mat. A least some of the couplers are looselyengaged between, and not rigidly coupled to, the cover and the mat toallow acceptable relative movement therebetween so that each cover andits associated mat may flex, expand and contract relative to the otherduring normal, typical or expected use conditions of the load-supportingsurface without decoupling the cover from its associated mat orundesirably damaging or deforming the cover or the mat.

In various embodiments, the present disclosure involves methods ofelectrically grounding a reusable load-supporting surface deployed on ornear the surface of the earth. The load-supporting surface includes atleast two mats, each mat having substantially planar respective top andbottom faces, multiple sides and at least one edge extending around eachside. The mats are configured to support the weight and movement ofpersonnel, vehicles and equipment thereupon. The method includespositioning one among a plurality of substantially planar, removable,electrically-conductive covers at least partially across the top surfaceof each mat without extending over any of the edges thereof. Each coveris constructed at least partially of electrically-conductive materialand configured to support the weight and movement of personnel, vehiclesand equipment thereupon. A plurality of selectively adjustable,releasable, couplers is loosely, releasably engaged a between each coverand its associated mat so that each cover stays positioned at leastpartially across the top face of its associated mat during use of theload-supporting surface and to allow the cover and mat to be moveablerelative to one another due to one or more environmental factors duringnormal, typical or expected use conditions of the load-supportingsurface without decoupling the cover from its associated mat and withoutundesirably damaging or deforming the cover or mat while allowing thecover and mat to support the weight and movement of personnel, vehiclesand equipment thereupon. At least one conductive interface of each coveris electrically coupled to at least one conductive interface of at leastone other mat in the load-supporting surface. At least one of the matsis grounded.

Accordingly, the present disclosure includes features and advantageswhich are believed to enable it to advance support surface technology.Characteristics and advantages of the present disclosure described aboveand additional features and benefits will be readily apparent to thoseskilled in the art upon consideration of the following detaileddescription of various embodiments and referring to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The following figures are part of the present specification, included todemonstrate certain aspects of various embodiments of this disclosureand referenced in the detailed description herein:

FIG. 1 is a perspective view of an exemplary load-supporting surfacinghaving a single exemplary mat equipped with an exemplaryelectrically-conductive cover to form an exemplary EPZ mat in accordancewith an embodiment of the present disclosure;

FIG. 2 is a perspective view of an exemplary load-supporting surfacinghaving multiple mechanically interconnected mats, some of which areequipped with an embodiment of an electrically-conductive cover andelectrically coupled together in accordance with the present disclosure;

FIG. 3 is a perspective view of an exemplary mat useful in aload-supporting surface in accordance with the present disclosure;

FIG. 4 is a top view of a portion of an exemplary load-supportingsurface useful in accordance with an embodiment of the presentdisclosure;

FIG. 5 is a top view of an exemplary mat equipped with an embodiment ofan electrically-conductive cover in accordance with the presentdisclosure;

FIG. 6A is a top view of an exemplary cut-out frame useful as part of anelectrically-conductive cover in accordance with an embodiment of thepresent disclosure;

FIG. 6B is a side view of the exemplary cut-out frame of FIG. 6A;

FIG. 6C is a perspective view of the exemplary cut-out frame of FIG. 6A;

FIG. 7A is a top view of an exemplary load-supporting surface having twomats equipped with electrically-conductive covers in accordance with anembodiment of the present disclosure;

FIG. 7B is a side view of the load-supporting surface of FIG. 7A;

FIG. 8 is an exploded view of a portion of the load-supporting surfaceof FIGS. 7A and B;

FIG. 9 is an exploded view of a portion of the load-supporting surfaceof FIG. 8;

FIG. 10A is a cross-sectional view of a portion of an embodiment of anouter frame useful as part of an electrically-conductive cover inaccordance with an embodiment of the present disclosure;

FIG. 10B is a cross-sectional view of another a portion of an embodimentof an outer frame useful as part of an electrically-conductive cover inaccordance with an embodiment of the present disclosure;

FIG. 11 is an assembly view of an exemplary bolted mat with which anelectrically-conductive cover may be used in accordance with anembodiment of the present disclosure;

FIG. 12A is a top view of an exemplary load-supporting surfacing havinga single mat equipped with an embodiment of an electrically-conductivecover in accordance with the present disclosure;

FIG. 12B is an exploded view of a portion of the load-supporting surfaceof FIG. 12A;

FIG. 13 is an exploded assembly view of an exemplary EPZ mat inaccordance with another embodiment of the present disclosure;

FIG. 14 is a perspective view of the exemplary EPZ mat of FIG. 13;

FIG. 15 is a top view of the exemplary EPZ mat of FIG. 13;

FIG. 16 is a top view of a first exemplary grate panel useful as part ofan embodiment of an electrically-conductive cover in accordance with thepresent disclosure;

FIG. 17 is a top view of a second exemplary grate panel useful as partof an embodiment of an electrically-conductive cover in accordance withthe present disclosure;

FIG. 18 is a top view of a third exemplary grate panel useful as part ofan embodiment of an electrically-conductive cover in accordance with thepresent disclosure;

FIG. 19 is a top view of an exemplary corner insert useful as part of anembodiment of an electrically-conductive cover in accordance with thepresent disclosure;

FIG. 20 is a perspective view of an exemplary load-supporting surfacewith exemplary EPZ mats having exemplary lip covers in accordance withan embodiment of the present disclosure;

FIG. 21 is an exploded perspective view of part of the exemplaryload-supporting surface of FIG. 20;

FIG. 22 is a perspective view of an exemplary short lip cover inaccordance with an embodiment of the present disclosure;

FIG. 23 is a perspective view of another exemplary short lip cover inaccordance with an embodiment of the present disclosure;

FIG. 24 is a perspective view of an exemplary corner short lip cover inaccordance with an embodiment of the present disclosure;

FIG. 25 is a perspective view of an exemplary long lip cover inaccordance with an embodiment of the present disclosure;

FIG. 26 is a perspective view of another exemplary long lip cover inaccordance with an embodiment of the present disclosure;

FIG. 27 is a perspective view of an exemplary load-supporting surfacewith exemplary EPZ mats having exemplary lip covers and an exemplarysafety barrier system in accordance with an embodiment of the presentdisclosure;

FIG. 28 is a perspective view of an exemplary electrical connection barshown used with an exemplary EPZ mat in accordance with an embodiment ofthe present disclosure;

FIG. 29 is a perspective view of the exemplary electrical connection barof FIG. 28;

FIG. 30 is a perspective view from above of the exemplary electricalconnection bar of FIG. 29 shown used at a first location on anembodiment of an EPZ mat in accordance with the present disclosure;

FIG. 31 is an exploded assembly view of the exemplary electricalconnection bar and EPZ mat of FIG. 30;

FIG. 32 is a perspective view from below of the exemplary electricalconnection bar and EPZ mat of FIG. 30;

FIG. 33 is a perspective view from above of the exemplary electricalconnection bar of FIG. 29 shown used at a second location on theexemplary EPZ mat shown in FIG. 30 in accordance with the presentdisclosure;

FIG. 34 is an exploded assembly view of the exemplary electricalconnection bar and EPZ mat of FIG. 30;

FIG. 35 is a perspective view from below of the exemplary electricalconnection bar and EPZ mat of FIG. 30;

FIG. 36 is a top view of an exemplary electrically-conductive cornerplate shown used with an embodiment of an EPZ mat in accordance with thepresent disclosure;

FIG. 37 is an exploded perspective view of two of the exemplaryelectrically-conductive corner plates of FIG. 36 shown mounted onadjacent exemplary EPZ mats and used to electrically connect them inaccordance with an embodiment of the present disclosure;

FIG. 38A is a top view of an exemplary load-supporting surface withmultiple exemplary EPZ mats each having the exemplaryelectrically-conductive corner plate of FIG. 36 mounted at each cornerthereof in accordance with an embodiment of the present disclosure;

FIG. 38B is an exploded view of part of the exemplary load-supportingsurface of FIG. 38A showing four adjacent exemplaryelectrically-conductive corner plates;

FIG. 39 is a top view two of the exemplary electrically-conductivecorner plates of FIG. 36 shown mounted on adjacent exemplary EPZ matsand used to electrically connect them to an exemplary testing unit inaccordance with an embodiment of the present disclosure;

FIG. 40 is a perspective view of the exemplary electrically-conductivecorner plate of FIG. 36;

FIG. 41 is a perspective view of another embodiment of anelectrically-conductive cover shown coupled to an exemplary mat to forman exemplary EPZ mats in accordance with another embodiment of thepresent disclosure;

FIG. 42A is a top view of the exemplary EPZ mat of FIG. 41;

FIG. 42B is a side view of the exemplary EPZ mat of FIG. 41;

FIG. 42C is a cross-sectional view of one of the exemplary EPZ mats ofFIG. 42A showing an exemplary coupler;

FIG. 43A is a top view of an exemplary load-supporting surface withmultiple of the exemplary EPZ mats of FIG. 41 in accordance with anembodiment of the present disclosure;

FIG. 43B is an exploded view of part of one of the exemplary EPZ mats ofFIG. 43A showing exemplary connection ports formed therein; and

FIG. 43C is an exploded view of part of the load-supporting surface ofFIG. 43A showing four of the exemplary EPZ mats electricallyinterconnected.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Characteristics and advantages of the present disclosure and additionalfeatures and benefits will be readily apparent to those skilled in theart upon consideration of the following detailed description ofexemplary embodiments of the present disclosure and referring to theaccompanying figures. It should be understood that the descriptionherein and appended drawings, being of example embodiments, are notintended to limit the claims of this patent application or any patent orpatent application claiming priority hereto. On the contrary, theintention is to cover all modifications, equivalents and alternativesfalling within the spirit and scope of this disclosure or any appendedclaims. Many changes may be made to the particular embodiments anddetails disclosed herein without departing from such spirit and scope.

In showing and describing preferred embodiments in the appended figures,common or similar elements are referenced with like or identicalreference numerals or are apparent from the figures and/or thedescription herein. The figures are not necessarily to scale and certainfeatures and certain views of the figures may be shown exaggerated inscale or in schematic in the interest of clarity and conciseness.

As used herein and throughout various portions (and headings) of thispatent application, the terms “invention”, “present invention” andvariations thereof are not intended to mean every possible embodimentencompassed by this disclosure or any particular claim(s). Thus, thesubject matter of each such reference should not be considered asnecessary for, or part of, every embodiment hereof or of any particularclaim(s) merely because of such reference. The terms “coupled”,“connected”, “engaged” and the like, and variations thereof, as usedherein and in the appended claims are intended to mean either anindirect or direct connection or engagement. Thus, if a first devicecouples to a second device, that connection may be through a directconnection, or through an indirect connection via other devices andconnections.

Certain terms are used herein and in the appended claims to refer toparticular components. As one skilled in the art will appreciate,different persons may refer to a component by different names. The useof a particular or known term of art as the name of a component hereinis not intended to limit that component to only the known or definedmeaning of such term (e.g. bar, connector, rod, cover, panel, bolt).Further, this document does not intend to distinguish between componentsthat differ in name but not function. Also, the terms “including” and“comprising” are used herein and in the appended claims in an open-endedfashion, and thus should be interpreted to mean “including, but notlimited to . . . .” Further, reference herein and in the appended claimsto components and aspects in a singular tense does not necessarily limitthe present disclosure or appended claims to only one such component oraspect, but should be interpreted generally to mean one or more, as maybe suitable and desirable in each particular instance.

Referring initially to FIG. 1, an exemplary mat 26 is shown including anelectrically-conductive cover 110 useful for allowing the mat 26 to beelectrically grounded in accordance with an embodiment of the presentdisclosure. In this illustration, the mat 26 serves as a load-supportingsurface 16 deployed on the ground or other surface. In otherembodiments, such as shown in FIG. 2, a larger load-supporting surface16 that includes multiple interconnected mats 26 is shown. In thatexample, the load-supporting surface 16 includes some mats 26 havingelectrically-conductive covers 110 and other mats 26 not havingelectrically-conductive covers. As used herein, the terms “EPZ mat” 112and variations thereof refer to a mat 26 having anelectrically-conductive cover 110. Thus, in this embodiment, whenmultiple interconnected EPZ mats 112 are used, eachelectrically-conducive cover 110 is useful for allowing theload-supporting surface 16 to be electrically grounded. In the presentembodiment, the load-supporting surface 16 (e.g. FIGS. 1 and 2) isreusable and capable of supporting the weight of personnel, vehiclesand/or equipment thereupon and moving there-across.

Referring to FIG. 3, the mats 26 may have any suitable form,construction and configuration. Some examples of mats 26 which may beused in various embodiments of the present disclosure are shown anddescribed in U.S. Pat. No. 5,653,551 to Seaux, entitled “Mat System forConstruction of Roadways and Support Surfaces” and issued on Aug. 5,1997, and U.S. Pat. No. 6,511,237 to Seaux et al., entitled“Interlocking Mat System for Construction of Load Supporting Surfaces”and issued on Jan. 28, 2003, both of which have a common Assignee as thepresent patent and the entire contents of which are hereby incorporatedby reference herein in their entireties. For example, each exemplary mat26 may weigh approximately 1,000 lbs., be designed to withstand up to600 psi in pure crush pressure placed thereupon, reduce point-to-pointground pressure on the ground 20 that may be caused by wheeled and/ortracked vehicles on the mat 26 or a combination thereof. In someembodiments, the mats 26 may be 14′×8′ DURA-BASE® mats currently sold bythe Assignee of this patent application.

If desired, the mats 26 may be used in connection with any of thecomponents and features described and shown in U.S. Pat. No. 9,132,996issued on Sep. 15, 2015 to Robertson and entitled “Crane-Mounted GrabHead”, U.S. Pat. No. 9,297,124 issued on Mar. 29, 2016 and entitled“Methods of Moving at Least One Mat With a Crane-Mounted Grab Head”,U.S. Pat. No. 7,370,452 issued on May 13, 2008 to Rogers and entitled“Mat Assembly for Heavy Equipment Transit and Support”, U.S. Pat. No.9,039,325 issued on May 26, 2015 to McDowell and entitled “LiquidContainment System for Use with Support Surfaces”, U.S. patentapplication Ser. No. 14/720,799, filed on May 24, 2015 and entitled“Liquid Containment System”, U.S. patent application Ser. No.14/336,163, filed on Jul. 21, 2014 and entitled “Apparatus and Methodsfor Providing Illuminated Signals from a Support Surface”, U.S.Provisional Patent Application Ser. No. 62/322,458 filed on Apr. 14,2016 and entitled “Apparatus, System and Methods for ProvidingAccessories on a Support Surface”, each of which has a common Assigneeas the present patent application and the entire contents of which arehereby incorporated by reference herein in their entireties.

Still referring to FIG. 3, in the illustrated embodiment, each mat 26 isflat, or planar, and constructed of impermeable material, such asthermoplastic. Other example mats 26 may be constructed entirely orpartially of wood, steel, steel-framed wood, aluminum, rubber, plastic,fiberglass, fiber reinforced plastic, recycled rubber or materials orany other desired material(s) or a combination thereof.

The exemplary mat 26 has a rectangular shape with an opposing pair ofshort sides 28, 30, an opposing pair of long sides 37, 38, and an edge44 extending along each side 28, 30, 37 and 38. In this particularexample, the first short side 28 and first long side 37 each have anupper lip 46 extending horizontally outwardly therefrom, forming theedge 44 and which will be spaced above the earth's surface, or ground,20 or other surface. The second short side 30 and second long side 38each have a lower lip 54 extending horizontally outwardly therefrombelow the edge 44 thereof and which will rest on or near the earth'ssurface, or ground, 20 or other surface. In this embodiment, a firstcorner 40 of the mat 26 is formed by the adjacent upper lips 46 and asecond corner 42 is formed by the adjacent lower lips 54.

The upper and lower lips 46, 54 may have any suitable size, shape,configuration and length. It should be understood, however, that theelectrically-conductive cover 110 of the present disclosure is notlimited to use with the above-described embodiments of mats 26 havingupper and/or lower lips 46, 54. For example, other embodiments of thecover 110 may be used in connection with mats 26 not having upper and/orlower lips 46, 54.

Still referring to the embodiment of FIG. 3, the respective upper andlower lips 46, 54 of different mats 26 are interconnectable with lockingpins 34 (e.g. FIGS. 4 & 5) releasably securable through correspondinglocking pin holes 32 formed therein. The locking pin holes 32 andlocking pins 34 may have any suitable form, construction andconfiguration. In this embodiment, the illustrated mats 26 include aplurality of locking pin holes 32, each configured to accept areleasable locking pin 34 (e.g. FIG. 4) therethrough. Each illustratedmat 26 may include a total of sixteen locking pin holes 32, eight formedin each of the upper and lower lips 46, 54.

Some examples of locking pins 34 which may be used in variousembodiments of the present disclosure are shown and described in U.S.Pat. No. 6,722,831 to Rogers et al., entitled “Fastening Device” andissued on Apr. 20, 2004, U.S. Pat. No. 8,388,291 to Rogers, entitled“Mat Lock Pin” and issued on Mar. 5, 2013, U.S. Pat. No. 9,068,584 toMcDowell et al, entitled and “Apparatus & Methods for Connecting Mats”and issued on Jun. 30, 2015, U.S. Provisional Patent Application Ser.No. 62/216,542, entitled “Apparatus for Connecting Mats and/or OtherComponents and Methods of Assembly and Use Thereof” and filed on Sep.10, 2015, each of which has a common Assignee as the present patentapplication and the entire contents of which are hereby incorporated byreference herein in its entirety.

In some embodiments, the locking pins 34 may form a fluid-tight sealaround, or in, the locking pin holes 32 within which they are engaged,such as the exemplary locking pin 34 illustrated and described in U.S.Pat. No. 9,068,584, U.S. Provisional Patent Application Ser. No.62/216,542, entitled “Apparatus for Connecting Mats and/or OtherComponents and Methods of Assembly and Use Thereof” and filed on Sep.10, 2015 and U.S. patent application Ser. No. 14/752,067 entitled“Adjustable Mat Locking Pin and Methods of Use Thereof” and filed onJun. 26, 2015, all of which have a common Assignee as the present patentapplication and the entire contents of which are hereby incorporated byreference herein in their entireties.

In the illustrated example, the locking pin holes 32 of the mats 26 havean oval-shape to accept an oval-shaped enlarged head 36 (e.g. FIGS. 4 &5) of the illustrated locking pins 34. It should be noted, however, thatthe present disclosure is not limited to use with the above-described orreferenced types and configurations of load-supporting surfaces 16, mats26, locking pins 34 and locking pin holes 32, or to the disclosures ofthe above-referenced patents and patent applications. Any suitableload-supporting surfaces 16 and mats 26, with or without any suitablelocking pins 34 and locking pin holes 32, may be used.

Now referring to FIG. 4, in some embodiments, a gap 22 may be formedbetween adjacent edges 44 of adjacent interconnected mats 26 in theload-supporting surface 16 and one or more seal members 10 may beincluded therein. For example, the seal member(s) 10 may provide afluid-tight seal in the gap 22 between adjacent mats 26 to preventliquid introduced onto the load-supporting surface 16 from seeping orflowing between and below the load-supporting surface 16.

Some embodiments of seal members 10 that may be used in the gaps 22 aredisclosed in U.S. Pat. No. 9,212,746 to McDowell, issued on Dec. 15,2015 and entitled “Apparatus and Methods for Sealing Between AdjacentComponents of a Load-Supporting Surface”, U.S. patent application Ser.No. 14/948,340, filed on Nov. 22, 2015 and entitled “Method of SealingBetween Adjacent Components of a Load-Supporting Surface With at LeastOne Closed-Cell Compressible Rubber Seal”, U.S. patent application Ser.No. 14/730,938, filed on Jun. 4, 2015 and entitled “Load-SupportingSurface with Actively Connected Gap Seals and Related Apparatus andMethods”, and U.S. patent application Ser. No. 14/733,324, filed on Jun.8, 2015 and entitled “Load-Supporting Surface with Interfacing Gap SealMembers and Related Apparatus and Methods”, all of which have a commonAssignee as the present patent application and the entire contents ofwhich are hereby incorporated by reference herein in their entireties.

The load-supporting surface 16 may include or be associated with othercomponents, and the seal member(s) 10 may also or instead be usedbetween any combination of mats 26 and other components associated withthe support surface 16. Some examples of such additional components thatmay be useful in connection with support surfaces 16, such as bermmembers, spacers, drive-over barriers, liquid drain assemblies, etc.,are shown and disclosed in U.S. Pat. No. 9,039,325 and U.S. patentapplication Ser. No. 13/790,916, and borehole edge seal systems such asshown and described in U.S. patent application Ser. No. 14/497,429,entitled “Apparatus and Methods for Sealing Around the Opening to anUnderground Borehole” and filed on Sep. 26, 2014 and U.S. patentapplication Ser. No. 14/666,584 entitled “Apparatus and Methods forMechanically Coupling a Sealing System Around the Opening to anUnderground Borehole” and filed on Mar. 24, 2015, both of which have acommon Assignee as the present patent application and the entirecontents of which are hereby incorporated by reference herein in theirentireties.

Referring back to FIG. 1, in accordance with the present disclosure, theelectrically-conductive cover 110 may have any suitable form,configuration and operation so that it can be used to allow theload-supporting surface 16 to be effectively and successfully groundedto the earth or other suitable structure. In the present embodiment, theelectrically-conductive cover 110 includes an outer frame 120 (see alsoFIGS. 6A-C) and an inner mesh portion 126. The frame 120 and meshportion 126 may be constructed of any suitable material and have anysuitable configuration that allows the load-supporting surface 16 to beeffectively and successfully grounded to the earth or other suitablestructure. For example, the frame 120 and mesh portion 126 may beconstructed at least partially of aluminum, stainless steel or otherelectrically-conductive material or a combination thereof. Theillustrated frame 120 is a welded rectangular steel frame providingrigidity for the cover 110 and preserving its integrity during use, suchas when the mat 112 is driven over by vehicles and machinery. In thisembodiment, the illustrated frame 120 is shown extending aroundsubstantially the entire mesh portion 126, but in other embodiments maynot extend around the entire mesh portion 126. The mesh portion 126 maybe constructed of any suitable at least partially metallic mesh orgrating, such as an aluminum mesh configuration that is sufficientlyelectrically conductive and sufficiently strong and durable to withstanduse as part of a load-supporting surface 16.

In this example, the frame 120 and mesh portion 126 are welded together.For example, as shown in FIG. 5, the perimeter edges 128 of the meshportion 126 may be welded to the top 122 of the frame 120. However, theframe 120 and mesh portion 126 may be coupled together or interconnectedin any other suitable manner.

Referring again to FIG. 1, the illustrated cover 110 also includes atleast one conductive interface 138 useful to electrically connect theEPZ mat 112 with one or more adjacent EPZ mats 112. The conductiveinterface(s) 138 may have any suitable form, configuration andoperation. In this embodiment, the cover 110 has an interface 138extending on each side 28, 30, 37 and 38 of the mat 26 to electricallyconnect the mat 26 with a corresponding respective adjacentinterconnected mats 26 (see e.g. FIGS. 2, 7-9). For example, the frame120 may be used to form an interface 138 on each side 28, 30, 37 and 38of the mat 26 that will abut, and thus electrically contact, aninterface 138 on a respective adjacent interconnected mat 26. In thepresent embodiment, on each side 28, 37 of the mat 26 having upper lips46, the frame 120 extends at least partially around the edge 44 thereofto form an underside face 156 (FIG. 9) which serves as the conductiveinterface 138 along that respective side of the mat 26 (See also FIGS. 8& 9). On each side 30, 38 of the mat 26 having lower lips 54, theexemplary frame 120 extends at least partially across the top 142 of thelower lip 54 to form an upward face 160 that serves as the conductiveinterface 138 along that respective side of the mat 26. As shown inFIGS. 8 & 9, the respective interfaces 138 of adjacent interconnectedEPZ mats 112 of this embodiment contact one another to form anelectrically conductive path therebetween. However, the presentdisclosure is not limited to the above type and arrangement ofinterfaces 138. For example, there may be interfaces on less than allsides 28, 30, 37 and 38 of the mat 26. For another example, theinterface(s) 138 may be disposed at specific locations on one or moresides of 28, 30, 37 and 38 of the mat 26 and/or at entirely differentlocations on the cover 110.

Referring to FIG. 5, if desired, a conductive booster 188 may be used inconnection with one or more interfaces 138 of each mat 112, such as toassist in ensuring a good electrical connection between adjacentinterconnected mats 112. The conductive booster 188 may have anysuitable form, configuration and operation. In the illustratedembodiment, the booster 188 is a metallic braided band 190 insertedbetween the corresponding underside face 156 (see e.g. FIG. 9) andupward face 160 of the frames 120 on a pair of adjacent interconnectedEPZ mats 112. The band 190 may, for example, have copper, aluminum orsteel braiding and extend between a portion or all of the length of theadjacent faces 156, 160. In this embodiment, the band 190 is a copperbraided band coupled, such as with rivets 198, screws or otherconnectors, to each upward face 160 of the frame 120 along its length.In other embodiments, multiple or few shorter sections of metallicbraided band 190 may be used.

Referring to FIGS. 12A-B, if desired, the mesh portion 126 may include acut-out 178 formed therein over each locking pin hole 32. For example,the cut-out 178 may be useful to electrically isolate a locking pin 34(e.g. FIGS. 4 & 5) placed in the locking pin hole 32 and preventelectrical conductivity between the cover 110 and the locking pin 34.The cut-out 178 may have any suitable form, configuration and operation.In this example, each cut-out 178 is spaced away from its correspondinglocking pin hole 32 to ensure sufficient electrical isolation. A cut-outframe 180 (see also FIGS. 6 & 8) constructed of any suitable material,such as one or more compatible electrically-conductive, metallicmaterials (e.g. aluminum, steel, etc.), is shown connected to, such asby weld, and covering the edges of the mesh portion 126 that form thecut-out 178. The cut-out frame 180 may, for example, provide stabilityaround the cut-out 178 and/or protect the exposed mesh portion 126 onthe edges of the cut-out 178. However, the cut-out frame 180, ifincluded, may be constructed of any other suitable material andconnected with the mesh portion 126 or mat 26 in any other suitablemanner.

At least one interconnected EPZ mat 112 of a load supporting surface 16may be grounded to the earth or other structure in any suitable manner.Referring back to FIG. 1, for example, a metal plate 166 may beelectrically connected, such as by weld, to the cover 110. In thisembodiment, the plate 166 is welded atop the mesh portion 126 and frame120 in one corner of the cover 110. A grounding cable 170 is shownelectrically connected between the plate 166 and a grounding rod 174that may be driven into the earth for electrically grounding the entireload-supporting surface 16. For example, any suitable commerciallyavailable grounding cable 170 and rod 174 and related components may beused, such as the grounding rod currently having Catalog No. 4370,stringing rod currently having Catalog No. 9738 and hanger studscurrently having Catalog Nos. 13190-1 and 13210 currently sold byHastings Hot Line Tools and Equipment.

In accordance with an embodiment of a method of assembly and use, theexemplary EPZ mat 112 may be assembled in any suitable manner. Forexample, referring to FIG. 1, the illustrated frame 120 and mesh portion126 are connected, such as by weld. If desired, the frame 120 and meshportion 126 may be painted with galvanized paint, such as to enhancetheir electrical conductivity and reduce or prevent corrosion. Theexemplary cover 110 is positioned on the generally planar top face, orsurface, 132 of the mat 26. As used herein, the terms “substantially”,“generally” and variations thereof means and includes (i) completely, or100%, of the referenced parameter, variable or value, and (ii) a rangeof values less than 100% based upon the typical, normal or expecteddegree of variation or error for the referenced parameter, variable orvalue in the context of the particular embodiment or use thereof, suchas, for example, 90-100%, 95-100% or 98-100%. Thus, the top surface 132of the exemplary mat 26, as referenced herein, does not include itslower lips 54 because the lower lips 54 are in a substantially differentplane. Similarly, the generally planar bottom face, or surface, 134 ofthe mat 26 (e.g. FIGS. 31, 42B), as referenced herein, does not includeits lower lips 54 because the lower lips 54 are in a substantiallydifferent plane.

In this embodiment, the edges 148, 150 of the illustrated frame 120 thatare aligned with the respective sides 28, 37 of the mat 26 may be atleast partially bent around the edges 44 thereof. The edges 152, 154 ofthe illustrated frame 120 that align with the respective sides 30, 38 ofthe mat 26 may be at least partially bent down and out over part of thetop 142 of the respective lower lip 54 (see also FIGS. 10A-B). In otherembodiments, one or more of the edges 148, 150, 152, 154 of the frame120 may be at least partially pre-formed or bent into its desired shape(see also FIGS. 10A-B) before placement of the cover 110 onto the mat26.

It should be noted that in other embodiments, the cover 110 may also orinstead extend at least partially across the generally planar bottomface, or surface, 134 (e.g. FIGS. 31, 42B) of the mat 26, or may extendacross only part of the top surface 132 of the mat 26. Likewise, theframe 120 may extend across a different portion, or all, of the lowerlip 54 of the sides 30, 38 of the mat 26 and may, if desired, extendaround the edges 44 thereof. Thus, the present disclosure is not limitedto a cover 110 having a mesh portion 126 that extends over the entiretop surface 132 of the mat 26 and a frame 120 that extends at leastpartially around the edges 44 of the sides 28, 37 and across at least aportion of the lower lip 54 of the sides 30, 38 of the mat 26. Any othersuitable configuration may be used.

If desired, the frame 120 and/or mesh portion 126 may be further coupledto the mat 26, such as with one or more connectors. For example,referring to FIG. 11, the mesh portion 126 (e.g. FIG. 1) may beconnected, such as by tack weld, to multiple of the bolt heads 70accessible at the top surface 132 of a “bolted” mat 26. Bolted mats 26may be formed, for example, by bolting two mat sections 21 a, 21 btogether with bolts 69 extended through aligned holes 29 formed in thesections 21 a, 21 b and secured with nuts 71, such as shown anddescribed in U.S. Pat. No. 6,511,257 to Seaux et al., entitled“Interlocking Mat System for Construction of Load Supporting Surfaces”and issued on Jan. 28, 2003 (e.g. FIG. 6 therein).

Referring again to FIG. 1, the booster(s) 188 and metal grounding plate166, if included on this particular mat 112, may be coupled to the cover110, such as described above, in advance or at any desired time afterthe cover 110 is coupled to the mat 26. If the load-supporting surface16 includes multiple of the exemplary EPZ mats 112 (e.g. FIGS. 2, 7),the overlapping lips 46, 54 of adjacent mats 26 are interconnected usinglocking pins 34 (e.g. FIGS. 4 & 5) as described above and in one or moreof the patents and patent applications previously incorporated herein byreference. In the referenced embodiments, the exemplary locking pins 34accurately position the adjacent mats 26 relative to one another andfirmly interconnect them, avoiding unnecessary rises and falls andhelping form a strong electrical connection therebetween.

As shown in FIGS. 7-9, upon interconnection of the illustrated mats 112,the interfaces 138 of adjacent mats 112 will contact one another toelectrically connect them together. Grounding of at least one mat 112will electrically ground the series of interconnected mats 112 in theload-supporting surface 16. A low resistivity path is formed betweeneach mat 112, allowing the flow of electrical charge and limiting therise of earth potential over the load-supporting surface 16. Electricaltests for the exemplary load-supporting surface 16 have demonstratedthat they successful pass electrical current from one mat 112 to thenext without substantial losses of electrical current or build-up ofsubstantial heat.

After use, the mats 112 of a multi-mat load-supporting surface 16 may bedisconnected from one another. In the present embodiment, the exemplarycover 110 of each EPZ mat 112 may be removed from its corresponding mat26 and replaced onto the same or another mat 26. For example, if thecover 110 suffers extensive damage during use, it can be removed,repaired and/or replaced. The mat 26 may be reused with or without thecover 110.

Referring now to FIG. 13, in another independent aspect of the presentdisclosure, the mesh portion 126 of the electrically-conductive cover110 may include multiple grate panels 200 for any desired purpose, suchas to provide ease of manufacture, handling, assembly, disassemblyand/or maintenance, assist in preserving the integrity of the cover 110during use or a combination thereof. The grate panels 200 may have anysuitable form, configuration, construction and components. Further, anydesired number of grate panels 200 may be used to form a mesh portion126. In the illustrated example, three grate panels 200 a, 200 b, 200 care interconnected to form the mesh portion 126 (See also FIGS. 14-15).In other embodiments, only two, four, five or more grate panels 200 maybe used.

The grate panels 200 may be constructed of any suitable materialsufficiently electrically conductive and strong and durable to withstanduse as part of a load-supporting surface 16. For example, the gratepanels 200 may be at least partially metallic mesh or grating, such asan aluminum mesh configuration.

Still referring to the embodiment of FIG. 13, if desired, the gratepanels 200 may be formed with cut-outs 178. For example, the gratepanels 200 may have cut-outs 178 extending to their edges and configuredto at least partially surround the locking pin holes 32 formed in theupper lips 46 of the associated mat 26 (See e.g. FIGS. 14-15). In thisembodiment, as shown in FIG. 16, the first grate panel 200 a includestwo short side cut-outs 178 a, one long side cut-out 178 b and one fullcorner cut-out 178 c. The second exemplary grate panel 200 b (e.g. FIG.17) includes two long side cut-outs 178 b and one partial corner cut-out178 d. The third illustrated grate panel 200 c (e.g. FIG. 18) includesone long side cut-out 178 b and one partial corner cut-out 178 d.

Referring FIGS. 13-15, one or more cut-out frames 180 may be used withthe grate panels 200. For example, cut-out frames 180 may be coupled toand cover the edges of the grate panels 200 that form the cut-outs 178.In this example, rectangular-shaped cut-out frames 180 a are shownwelded to the grate panels 200 over all of the illustrated cut-outs 178,except the full corner cut-out 178 c of the first grate panel 200 a (atthe first corner 40 of the mat 26) is shown having a U-shaped cut-outframe 180 b (See also FIGS. 14-15).

In some embodiments, the grate panels 200 may be interconnected, and inother embodiments may not be interconnected. When interconnected, thegrate panels 200 may be interconnected in any suitable manner. Forexample, the grate panels 200 may be welded together at their adjacentedges, clamped together or coupled using any other suitable couplingmechanism(s). In the illustrated embodiment, the cover 110 includes oneor more internal frame members 206 for interconnecting adjacent gratepanels 200. For example, a first illustrated internal frame member 206 amay be welded atop adjacent edges of the first and second grate panel200 a, 200 b, and a second internal frame member 206 welded atopadjacent edges of the second and third grate panel 200 b, 200 c (Seealso FIGS. 14-15). In other embodiments, the internal frame members 206may be welded underneath the adjacent panels 200, or connected to thepanels 200 in any other suitable manner. If desired, the internal framemembers 206 may have additional purposes, such as to add strength and/orstiffness to the cover 110 and assist in preserving its integrity duringuse.

The internal frame members 206 may have any suitable form, configurationand components. In this example, the internal frame members 206 areelongated. As used herein, the terms “elongated” and variations thereofmean an item having an overall length that is greater than its averagewidth. The illustrated first internal frame member 206 a is longer thanthe exemplary second internal frame member 206 b, which intersects theillustrated adjacent partial corner cut-outs 178 d of the grate panels200 b, 200 c.

The internal frame members 206 may have any suitable construction. Forexample, the internal frame members 206 may be constructed at leastpartially of aluminum, steel, stainless steel or other sufficientlyelectrically-conductive material or a combination thereof, provide thedesired strength, durability, rigidity and flexibility for the cover 110to preserve its integrity during use, such as when the EPZ mat 112 isdriven over by vehicles and machinery or other suitable purpose.

If desired, one or more of the ends 207 of the internal frame members206 may be interconnected with the outer frame 120 or one or morecut-out frames 180, such as by weld, clamp or other mechanism. In theembodiment of FIG. 14, both ends 207 of the internal frame members 206 aare welded to the adjacent portions of the outer frame 120, while oneend of the internal frame member 206 b is welded to the adjacent outerframe 120 and its other end welded to the adjacent cut-out frame 180.

Referring still to FIGS. 13-15, in another independent aspect of thepresent disclosure, the mesh portion 126 (e.g. grate panels 200) may beconnected to the mats 26 with one or more couplers 62. The couplers 62may have any suitable form, configuration, constructions, components andoperation. In this embodiment, for example, the couplers 62 includebolts 69 extending into, but not through, the mat 26. Also, the meshportion 126 of the exemplary cover 110 of this embodiment is not weldedto the bolts 69. A washer 73 may be sandwiched between each exemplarybolt head 70 and the upper surface of the exemplary mesh portion 126. Inother embodiments, the couplers 62 may extend through the mat 26 and maybe releasably secured to the mat 26, such as with one or more nuts 302(e.g. FIG. 42C) or other connector(s). Any desired number of couplers 62may be included. In this example, fifteen bolts 69 are shown extendinginto the mat 26 at predetermined locations; however, more or lesscouplers 62 may be used.

Referring to FIG. 13, in some embodiments, a space 208 is formed betweenthe adjacent upper faces 160 of the frame 120 proximate to the secondcorner 42 of the mat 26. In such instances, if desired, a corner insert210 may be affixed to the frame 120 and/or mat 26 in the space 208. Thecorner insert 210 may have any suitable form, shape, configuration andoperation. In this example, the corner insert 210 is triangular, orstar-shaped (e.g. FIG. 19), and fills in the space 208. If desired, thecorner insert 210 may engage the frame 120 and/or mat 26, such as toassist in securing the frame 120 to the mat 26. In this example, thecorner insert 120 may be welded to the adjacent edges of the frame 120,such as to assist in preserving the integrity of the frame 120 at thatlocation. Also, if desired, one point 212 of the corner insert 210 maybe configured to stab into the mat 26 to assist in securing the frame120 to the mat 26.

Referring now to FIG. 20, in another independent aspect of the presentdisclosure, in some situations, it may be desirable to havesubstantially all upwardly facing surfaces of the EPZ mats 112 in theload-supporting surface 16 covered with electrically-conductivematerial. This may be desirable, for example, when the user of theload-supporting surface 16 having EPZ mats 112 desires to minimizeexposed surfaces of mats 26 (e.g. exposed thermoplastic or othermaterial) in the load-supporting surface 16. For example, theelectrically-conductive covers 110 on mats 112 with exposed lower lips54 (e.g. disposed on the perimeter 18 of the load supporting surface 16)may extend across the lower lips 54 to fully cover the mats 112. Foranother example, in the illustrated embodiment, one or moreelectrically-conductive lip covers 220 are used on one or more of thelower lips 54 of one or more of the mats 26. For example, the mats 112with lower lips 54 disposed on the perimeter 18 of the load supportingsurface 16 may be equipped with lip covers 220.

The lip cover 220 may have any suitable form, configuration,construction, components, location and operation. For example, referringto FIG. 22, the lip cover 220 may include a lip cover frame 224 and alip cover mesh portion 230. The lip cover frame 224 may have any or allof the features, characteristics and details of the outer frame 120 asdescribed above and shown in the appended figures, and the lip covermesh portion 230 may have any or all of the features, characteristicsand details of the mesh portion 126 as described above and shown in theappended figures. For example, the lip cover frame 224 and lip covermesh portion 230 may be constructed at least partially of aluminum,steel, stainless steel or other sufficiently electrically-conductivematerial or a combination thereof that allows the associated lower lip54 to be effectively grounded to the earth or other suitable structure,to provide sufficient strength, durability, rigidity and flexibility topreserve the integrity of the lip cover 220 during use as part of aload-supporting surface 16 or other suitable purpose. In someembodiments, the lip cover mesh portion 230 may be constructed at leastpartially of metallic mesh or grating, such as an aluminum meshconfiguration, and the lip cover frame 224 may be a welded rectangularsteel frame.

Still referring to FIG. 22, in this embodiment, the lip cover frame 224includes (i) a generally flat, elongated, inner frame member, or portion226, (ii) a generally flat end frame member, or portion, 225 on each endof the lip cover 220 and (iii) an elongated, L-shaped, outer framemember, or portion, 227, all rigidly coupled together. The outer portion227 of the illustrated lip cover frame 224 is designed to extend atleast partially over the respective edge 234 of the lower lip 54 of thecorresponding mat 112 (e.g. FIG. 21) when the lip cover 220 is coupledto the mat 112.

In some embodiments, the lip cover frame 224 may be coupled to the lipcover mesh portion(s) 230 and in other embodiments may not. When coupledtogether, any suitable coupling mechanism(s) or technique may be used.In the illustrated example, the lip cover frame 224 and lip cover meshportion 230 are welded together. For example, the lip cover frame 224may be welded atop the edges of the lip cover mesh portion 230. In otherembodiments, the lip cover mesh portion 230 may be welded atop the lipcover frame 224 or coupled in any other suitable manner.

Referring now to FIG. 21, if desired, the lip cover 220 may include atleast one lip cover conductive interface 238 useful to electricallyconnect the lip cover 220 to one or more other components, such as thecover 110 of the same mat 26, the cover 110 of one or more other mats26, another one or more lip covers 220 of the same mat 26 and/or one ormore other mats 26, any other desired component(s) or a combinationthereof. The lip cover conductive interface(s) 238 may have any suitableform, configuration and operation. For example, the lip cover conductiveinterface 238 may include a connector for electrically coupling the lipcover 220 to another component. In this embodiment, at least one lipcover conductive interface 238 is configured to electrically connect thelip cover 220 to the cover 110 of the same mat 26. The illustrated lipcover conductive interface 238 extends at least partially along theinner portion 226 of the lip cover frame 224 and contacts the cover 110to allow electrical conductivity therebetween. For example, the bottomsurface 228 of the inner portion 226 of the illustrated lip cover frame224 overlays and contacts the upward face 160 (and conductive interface138) of the frame 120 to form an electrically-conductive paththerebetween. However, the lip cover conductive interface 238 may haveany other desired form.

Referring back to FIG. 20, in the illustrated embodiment, a distinct lipcover 220 is positionable on the each lower lip 54 of the mat 26. Forexample, a short lip cover 250 may be configured to extend acrosssubstantially the length of the lower lip 54 at the second short side 30of the mat 26, and a long lip cover 260 may be configured to extendacross substantially the length of the lower lip 54 extending from thesecond long side 38 of the mat 26. For any exemplary mat 26 having itscorner 42 (formed between adjacent lower lips 54) exposed, either theshort lip cover 250 or the long lip cover 260 may be shorter than theother respective covers 250, 260. In this embodiment, the corner shortlip cover 254 (e.g. FIG. 24) is shorter than the other short lipcover(s) 250 (e.g. FIGS. 22-23).

If desired, the lip covers 220 may be formed with one or more cut-outs178, such as to allow access to one or more locking pin holes 32 on thelower lip 54 of the mat 26, or for any other purpose. Also if desired,one or more cut-out frames 180 may be used with the lip covers 220. Forexample, cut-out frames 180 may be coupled to and cover the edges of thelip covers 220 that form the cut-outs 178.

Any desired number of cut-outs 178 and cut-out frame 180 may beincluded. In the present embodiment, since the exemplary mats 26 (e.g.FIG. 3) each have three locking pin holes 32 on the lower lip 54 at thesecond short side 30 of the mat 26, the short lip cover 250 (e.g. FIG.22) may be configured to include three cut-outs 178 to allow access toall of the locking pin holes 32. For another example, in FIG. 23, theshort lip cover 250 includes only two cut-outs 178 to allow access totwo of the locking pin holes 32 (See also FIG. 20). Similarly, since theexemplary mats 26 (e.g. FIG. 3) each have six locking pin holes 32 onthe lower lip 54 at the second long side 38 of the mat 26, the long lipcover 260 (e.g. FIG. 25) may be configured to include six cut-outs 178to allow access to all of the locking pin holes 32. For another example,in FIG. 26, the long lip cover 260 includes only three cut-outs 178 toallow access to three of the locking pin holes 32 (See also FIG. 20).

Other embodiments may include fewer cut-outs 178 on the lip covers 220.It may be necessary or desirable to allow access to only some of thelocking pin holes 32 in the respective lower lips 54 through the lipcovers 220 depending upon the expected use of the locking pin holes 32.For example, when all the locking pin holes 32 of the lower lips 54 arenot needed, fewer cut-outs 178 may be desirable, such as to preserve theintegrity, strength and rigidity of the lip covers 220. For anotherexample, in embodiments where the lip covers 220 are secured to the mats26 via one or more locking pin holes 32, only those locking pin holes 32needed to adequately secure the lip covers 220 to the mats 26 may bemade accessible though the cut-outs 178. For another example, in someembodiments, such as load-supporting surfaces 16 having mats 26 withoutlocking pin holes 32, the lip covers 220 may not include any cut-outs178.

Referring now to FIG. 27, the lip covers 220 may be coupled to the mat26 in any suitable manner. For example, the lip cover mesh portions 230may be secured with couplers 62, such as bolts 69, similarly asdescribed above with respect to mesh portions 126 and mesh grate panels200. For another example, the lip cover frame 224 may engage or wraparound one or more edges of the associated lower lip 54. For still afurther example, the lip cover 220 may be coupled to the cover 110disposed on the same mat 26. In the present embodiment, the lip covers220 are shown coupled to the illustrated mats 26 by one or more uprightmembers 310, each releasably engaging a locking pin hole 32 in one ofthe respective lower lips 54 of the associated mats 26. The uprightmember 310 may have any desired components, configuration, operation anduse. For example, the upright member 310 may be, or include, a bar,post, frame or the like. In this embodiment, the upright member 310 is apole 312 useful to support one or more signs, fences or safety barriers,and may be constructed of any suitable material, such as aluminum, steelor fiberglass. The upright member 310 may be releasably engaged with thelocking pin hole 32 in any suitable manner. For example, an uprightmember support system 320, such as the system 300 disclosed in U.S.patent application Ser. No. 15/132,410, filed on Apr. 19, 2016 andentitled “Apparatus, System and Methods for Supporting One or MoreUpright Items from a Support Surface”, may be used. In the illustratedembodiment, multiple upright member support systems 320 are shownsupporting multiple poles 312 as part of a safety barrier system 420.U.S. patent application Ser. No. 15/132,410 has a common Assignee as thepresent patent and the entire contents of Ser. No. 15/132,410 are herebyincorporated by reference herein in its entirety.

Now referring to FIG. 28, in another independent aspect of the presentdisclosure, an electrical connection bar 270 may be used with one ormore EPZ mats 112 in the load-supporting surface 16. The electricalconnection bar 270 may be used for any suitable purpose, such asgrounding the EPZ mat 112 or load-supporting surface 16, electricallyconnecting the EPZ mat 112 or load-supporting surface 16 to testingmonitoring, measuring or other equipment, electrically interconnectingmultiple EPZ mats 112 or a combination thereof. In the illustratedembodiment, a grounding rod 174 for grounding the load-supportingsurface 16 is shown releasably, electrically coupled to the electricalconnection bar 270 via a grounding cable 170 and an electrical connector288. In some embodiments, the electrical connection bar 270 may serve aspart of the conductive interface(s) 138 useful to releasably,electrically connect the EPZ mat 112 with one or more other EPZ mats112, such as with the use of an electrical connector 288 or otherelectrically-conductive wire, cable, bar or other electrical connectioncomponent(s).

The electrical connection bar 270 may be releasably coupled to one ormore electrical connection components (e.g. electrical connector(s) 288,wires, cables, pins, testing, monitoring, measuring or other equipment,etc.) in any suitable manner. For example, the electrical connection bar270 may include one or more connection ports 278. The connection port278 may have any suitable form and configuration. In this embodiment,the connection port 278 is an orifice 280 formed into the bar 270. Theillustrated connection ports 278 face generally horizontally on theconnector bar 270, such as to allow ease of electrical connectiontherewith, maintain a low profile of the electrical connectioncomponents (e.g. electrical connector(s) 288, grounding cables 170,etc.) above the top surface 132 of the mat 112, minimize the risk ofundesired or accidental decoupling of electrical connection componentsor other desired purpose. If desired, multiple connection ports 278(e.g. FIG. 29) may be included, such to allow flexibility and multipleoptions in the position(s) and quantity of electrical connections thatcan be made to the EPZ mat 112 or other desired purpose.

Referring to FIGS. 28-29, the electrical connection bar 270 may beconstructed of any suitable material, such as aluminum, steel, stainlesssteel, other electrically-conductive material or a combination thereof,and have any suitable form, configuration and operation. In thisembodiment, the electrical connection bar 270 is a section of rigidangle-iron 271 sufficiently strong and durable to withstand use as partof a load-supporting surface 16. The exemplary bar 270 is elongated,such as to provide space for multiple connection ports 278, maintain alow profile above the top surface 132 of the mat 112, be sufficientlysecurable to the mat 112 to preserve its electrical contact therewithduring use of the load-supporting surface 16 or other desired purpose.For still a further example, the electrical connection bar 270 may beconfigured and positioned to allow cables (e.g. the grounding cable170), wire and the like to be coupled to the EPZ mat 112 orload-supporting surface 16 without substantial risk of undesirablecoiling or being undesirably draped over or across a substantial portionof one or more electrically-conductive covers 110 in the load-supportingsurface 16.

Referring now to FIGS. 30-32, the electrical connection bar 270 may beconnected to the EPZ mat 112 in any suitable manner. For example, thebar 270 may be welded to the frame 120, mesh portion 126, one or morecut-out frames 180 of the exemplary cover 110 or a combination thereof.For another example, the electrical connection bar 270 may be releasablycoupled to one or more locking pin holes 32 of the mat 26, such as toallow desired positioning of the electrical connection components, orelectrical connection with an adjacent mat 112 or other component(s), ata side or corner of the mat 26 or load-supporting surface 16. In theillustrated embodiment, the electrical connection bar 270 is configuredto be releasably connected and electrically coupled to the EPZ mat 112proximate to its first corner 40, such as to allow desired positioningof the electrical connection components, or electrical connection withan adjacent mat 112 or other component(s), at a side or corner of themat 26 or load-supporting surface 16. The exemplary electricalconnection bar 270 is configured so that when it is coupled to the EPZmat 112, one leg of the angle-iron 271 is substantially verticallyoriented and the connection ports 278 formed therein are orientedgenerally horizontally. The other illustrated leg of the angle-iron 271is substantially horizontally oriented to abut and make electricalcontact with the electrically-conductive cover 110 and align at leastone anchor hole 272 formed therein (e.g. FIG. 31) over a locking pinhole 32 of the mat 26.

In the illustrated embodiment, the electrical connection bar 270 isshown releasably coupled to two locking pin holes 32 of the EPZ mat 112.For example, as shown in FIG. 31, at each such locking pin hole 32, abolt 282 (or other connector, such as a pin, screw etc.) may extendthrough an anchor hole 272 in the connector bar 270 then through thelocking pin hole 32. The exemplary bolt 282 (or other connector) may,for example, be releaseably secured below the mat 112 to a threadedanchor base 284 placed below the locking pin hole 32. If desired, thebolt 282 may threadably engage a nut 286 welded to, or otherwiseextending from, the upper surface of the anchor base 284. As shown inFIG. 32, under the mat 26, the exemplary anchor base 284 releasablysecures the electrical connection bar 270 to the mat 26 at leastpartially around the locking pin hole 32. However, any other method andmechanism for coupling the bar 270 to one or more mats 26 may be used.

If desired, the electrical connection bar 270 may be useful at differentlocations on the mat 112 to provide flexibility in the location ofelectrical connection components or other desired purpose. In thisexample, the electrical connection bar 270 may be coupled to the twolocking pin holes 32 closest to the first corner 40 of the mat 26 oneither the first long side 37 (FIGS. 30-32) or the first short side 28(FIGS. 33-35) of the mat 26. However, in other embodiments, theelectrical connection bar 270 may be coupled to different locking pinholes 32 or any other desired portion or component of the mat 112 orload supporting surface 16.

Referring back to FIG. 28, the electrical connection bar 270 may beelectrically coupled to the EPZ mat 112 in any desired manner. In thisexample, the bar 270 abuts and electrically contacts theelectrically-conductive cut-out frames 180 of the cover 110. The bar 270may also, or instead, abut and electrically contact the mesh portion 126and/or frame 120 of the cover 110. In other embodiments, the bar 270 maybe electrically coupled to a different part or component of the mat 112or load-supporting surface 16.

When included, the electrical connector(s) 288 useful for electricallycoupling the electrical connection bar 270 (or other component(s) of themat 112) to one or more other component or mat 112 may have any suitableform, configuration and construction. In this embodiment, the electricalconnector 288 is a rigid bolt 289 coupled to the bar 270. If desired,the electrical connector 288 may be flexible, such as to allow relativemovement between the respective mat 112 (or cover 110) and othercomponent without disconnecting therefrom. Other examples of electricalconnectors 288 may include one or more pin, flexible member, copperwires, jumper cables 292 (e.g. FIG. 37), braided steel strips 298 (e.g.FIG. 43C) and the like. If desired, the electrical connector 288 may becoupled with slack (e.g. FIG. 37), such as to allow relative movementbetween the mat 112 (or cover 110) and other component withoutdisconnecting therefrom. In some embodiments, the electrical connector288 may serve as part of the conductive interface(s) 138 between mats112.

Now referring to FIGS. 36-37, in another independent aspect of thepresent disclosure, an electrically-conductive corner plate 290 may beused with one or more EPZ mats 112 in the load-supporting surface 16.The corner plate 290 may be used for any suitable purpose, such as toreleasably, electrically interconnect multiple EPZ mats 112, ground theEPZ mat 112 or load-supporting surface 16, electrically connect the EPZmat 112 or load-supporting surface 16 to testing, monitoring, measuringor other equipment, or a combination thereof. For example, the cornerplate 290 may be useful to electrically connect the EPZ mat 112 to oneor more other EPZ mats 112, serving as part of the conductiveinterface(s) 138 (e.g. FIG. 37). In some embodiments, the corner plate290 may also or instead be used in addition to one or more other engagedconductive interfaces 138 (e.g. FIG. 9) of two or more electricallycoupled mats 112 to ensure effective electrical interconnection and/orgrounding of the mats 112 and/or other components in the load-supportingsystem 16. For another example, in FIG. 39, the corner plates 290 onadjacent mats 112 are shown releasably electrically coupled to a testingunit 294, such as a 4-wire kelvin-resistance measuring device.

The corner plate 290 may be constructed of any suitable material, suchas aluminum, steel, stainless steel, other material or a combinationthereof that is sufficiently electrically-conductive and, if desired,strong and durable enough to be useful in the load-supporting surface16.

Referring now to FIGS. 39-40, the corner plate 290 may have any suitableform, configuration and operation. For example, the corner plate 290 maybe configured to allow ease of electrical connection therewith, maintaina low profile of the electrical connection components (e.g. electricalconnector(s) 288, cables, etc.) above the top surface 132 of the mat112, minimize the risk of undesired or accidental decoupling ofelectrical connection components or other desired purpose. In thisembodiment, the corner plate 290 is generally flat, L-shaped andconfigured to be physically and electrically coupled, such as by weld,to a corner of the EPZ mat 112, such as to allow desired positioning ofthe electrical connection components or electrical connection with anadjacent mat 112 or other component(s) at a side or corner of the mat 26or load-supporting surface 16. For example, as shown in FIGS. 38A-B, thecorner plate 290 may be welded to the corner of the frame 120 of theelectrically-conductive cover 110. If desired, the corner plate 290 maybe coupled to each corner of the frame 120. In other embodiments, thecorner plate 290 may be coupled to only select corners of the frame 120or to any other desired location on the frame 120, mesh portion 126, oneor more cut-out frames 180 or other component of the cover 110 or EPZmat 112, or a combination thereof, such as by weld,electrically-conductive mechanical connector (e.g. pin, bolt, screw) orother method.

Referring back to FIGS. 36-37, the exemplary corner plate 290 may bereleasably coupled to one or more electrical connection components (e.g.electrical connector(s) 188, wires, cables, grounding, testing,monitoring, measuring or other equipment, etc.) in any suitable manner.For example, the corner plate 290 may include one or more connectionports 278. The connection port 278 may have any suitable form andconfiguration. In this embodiment, the connection port 278 is a threadedorifice 280 formed in the corner plate 170 and configured to receive anysuitable electrical connector 288 or other connection component, such asa bolt, pin, screw, strip, wire, etc. In FIG. 39, for example, a testingunit 294 is releasably secured in electrical contact with the cornerplates 290 of adjacent mats 112 by electrical connectors 288 (e.g. bolts296) threadably engaged with orifices 280 of the respective plates 170.

If desired, multiple connection ports 278 may be included, such to allowflexibility and multiple options in the position(s) and quantity ofelectrical connections that can be made to the EPZ mat 112 or otherdesired purpose. In this embodiment, the corner plate 290 includes fourconnection ports 278, but other embodiments may include less (one, twoor three) or more (five, six, etc.) connection ports 278.

As mentioned above, if desired, one or more electrical connectors 288may be used to secure the exemplary corner plate 290 to anothercomponent. In FIG. 37, for example, the electrical connectors 288include a jumper cable 292 and two bolts 296 releasably electricallycoupled to orifices 280 of the respective corner plates 290 of adjacentmats 112 to electrically couple the mats 112 together. In this example,the electrical connectors 288 serve as part of the conductiveinterface(s) 138 between the mats 112. If desired, the jumper cable 292or other electrical connector 288 may be coupled to the corner plate 290with slack, such as to allow relative movement between the respectivemats 112 (or covers 110) without disconnecting the therefrom or otherdesired purpose.

Now referring to FIG. 41, in another independent aspect of the presentdisclosure, the EPZ mat 112 may be configured and arranged to allow somerelative movement between the mat 26 and the cover 110, while at leastsubstantially preserving the integrity and desired functioning of themat 26 and cover 110. For example, the cover 110 may be constructed andconfigured to be rigid enough to perform as part of the EPZ mat 112 andload-supporting surface 16 (e.g. as described above) and flexible enoughto bend, flex, expand, contract or a combination thereof relative to themat 26, such as due to one or more environmental factors (e.g. changingtemperatures), movement of personnel, vehicles and/or equipment acrossthe load-supporting surface 16 or other factors during normal, typicalor expected use conditions of the load-supporting surface 16 and withoutdecoupling them or undesirably damaging or deforming either the cover110 or mat 26. The terms “flexibly constructed” and variations thereofas used herein with respect to the cover 110 or any component thereofmeans the cover 110 (or component(s) thereof) is constructed andconfigured to be rigid enough to perform as part of the EPZ mat 112 andload-supporting surface 16 (e.g. as described above) and flexible enoughto bend, flex, expand, contract or a combination thereof relative to themat 26, such as due to one or more environmental factors (e.g. changingtemperatures), movement of personnel, vehicles and/or equipment acrossthe load-supporting surface 16 or other factors during normal, typicalor expected use conditions of the load-supporting surface 16, withoutdecoupling them or undesirably damaging or deforming either the cover110 or mat 26.

For another example, the cover 110 may be coupled to the mat 26sufficiently rigidly to perform as part of the EPZ mat 112 andload-supporting surface 16 (e.g. as described above) and alsosufficiently flexibly to allow the mat 26 to bend, flex, expand,contract or a combination thereof relative to the cover 110, such as dueto one or more environmental factors (e.g. changing temperatures),movement of personnel, vehicles and/or equipment across theload-supporting surface 16 or other factors during normal, typical orexpected use conditions of the load-supporting surface 16 and withoutdecoupling them or undesirably damaging or deforming either the cover110 or mat 26. The terms “flexibly coupled” and variations thereof asused herein with respect to the cover 110 or any component thereof meansthe cover 110 (or component(s) thereof) is coupled to the mat 26sufficiently rigidly to perform as part of the EPZ mat 112 andload-supporting surface 16 (e.g. as described above) and sufficientlyflexibly to allow the mat 26 to bend, flex, expand, contract or acombination thereof relative to the cover 110, such as due to one ormore environmental factors (e.g. changing temperatures), movement ofpersonnel, vehicles and/or equipment across the load-supporting surface16 or other factors during normal, typical or expected use conditions ofthe load-supporting surface 16, without decoupling them or undesirablydamaging or deforming either the cover 110 or mat 26. The terms“acceptable relative movement” and variations thereof as used hereinwith respect to the cover 110 (or any components thereof) and mat 26 (orany components thereof) means movement of either or both the cover 110and mat 26 (or the referenced component(s) thereof) relative to theother, such as due to one or more environmental factors (e.g. changingtemperatures), movement of personnel, vehicles and/or equipment acrossthe load-supporting surface 16 or other factors during normal, typicalor expected use conditions of the load-supporting surface 16, withoutdecoupling them, undesirably damaging or deforming either the cover 110or mat 26 or substantially diminishing the desired functioning of themat 112 in the load-supporting surface 16 (e.g. such as describedabove).

Still referring to FIG. 41, the cover 110 may be configured to allowacceptable relative movement between the cover 110 and mat 26 in anysuitable manner. For example, the cover 110 may not extend around anyedges 44 of the mat 26 (See also FIGS. 42A-B). In the illustratedembodiment, the cover 110 is generally planar and extends at leastpartially over only the top surface 132 of the mat 26. Unlike theexemplary frame 120 shown in FIGS. 8-9, the frame 120 in this embodimentdoes not extend around the edges 44 of the exemplary mat 26 on each side28, 37 having upper lips 46 or across any part of the top 142 of thelower lips 54 of the exemplary mat 26. Also the frame 110 of thisembodiment does not have any underside faces 156 (e.g. FIG. 9) or upwardfaces 160 that serve as conductive interfaces 138 in the mannerdescribed with respect to the embodiment of FIGS. 8-9.

Referring now to FIGS. 42A-C, if desired, the cover 110 may be flexiblycoupled to the mat 26 to allow acceptable relative movement in anysuitable manner. In the present embodiment, a plurality of couplers 62releasably secures the cover 110 to the mat 26. The illustrated couplers62 include bolts 69, but may include any other form of couplers (e.g.clips, pins, rods, screws, etc.). Referring to FIG. 42C, at least someof the exemplary couplers 62 (i) extend over and through the cover 110(e.g. over the frame 120 and/or mesh portion 126), (ii) include anelongated body that extends through an aperture 300 formed in the mat 26and (iii) are releasably secured to the bottom surface 134 of the mat 26with at least one nut 302 or other suitable releasable, adjustableanchor. In some embodiments, the couplers 62 may be the onlyinterconnection of the cover 110 and the associated mat 26. If desired,to allow for some acceptable relative movement, at least some of thecouplers 62 may be loosely engaged between, and not rigidly coupled(e.g. by weld) to the cover 110 or mat 26. As shown in FIG. 42C, forexample, the inner diameter 304 of the exemplary aperture 300 may begreater than the outer diameter 306 of the elongated body of the coupler62, allowing some side-to-side relative movement between the mat 26, thecoupler 62 and the cover 110. For another example, the nuts 302 (orother suitable anchors) may not be fully tightened against the bottomface 134 of the mat 26 to allow some relative up-and-down movementbetween the mat 26, the coupler 62 and the cover 110. However, the cover110 and/or mat 26 may be configured to allow for acceptable relativemovement therebetween in any other suitable manner.

Now referring to FIGS. 43A-C, in another independent aspect of thepresent disclosure, the electrically-conductive cover 110 may be formedwith one or more connection ports 278 to releasably, electricallyinterconnect multiple EPZ mats 112, ground the EPZ mat 112 orload-supporting surface 16, electrically connect the EPZ mat 112 orload-supporting surface 16 to testing, monitoring, measuring or otherequipment, other desired purpose or a combination thereof. For example,in this embodiment, as shown in FIG. 43C, the illustrated connectionports 278 formed in adjacent mats 112 are used to electricallyinterconnect adjacent EPZ mats 112 and thus serve as part of theconductive interfaces 138 of the mats 112. In other embodiments, one ormore connection bars 270 (e.g. FIG. 28), corner plates 290 (e.g. FIG.36), other forms of conductive interfaces 138 or a combination thereofmay be used.

The connection ports 278 formed in this embodiment of the cover 110 mayhave any suitable form, configuration, construction and operation. Forexample, the connection ports 278 may be configured to allow ease ofelectrical connection therewith, maintain a low profile of theelectrical connection components (e.g. braided steel strips 298) abovethe top surface 132 of the mat 112, minimize the risk of undesired oraccidental decoupling of electrical connection components or otherdesired purpose. In this embodiment, the connection port 278 is athreaded orifice 280 formed in a corner of the EPZ mat 112, such as toallow desired positioning of the electrical connection components, orelectrical connection with an adjacent mat 112 or other component(s), ata side or corner of the mat 26 or load-supporting surface 16. Forexample, the connection port 278 may be formed in the corner of theframe 120 of the electrically-conductive cover 110. If desired,connection ports 278 may be formed in each corner of the frame 120. Inother embodiments, one or more connection ports 278 may be formed inonly select corners of the frame 120 or at any other desired location onthe frame 120, mesh portion 126, one or more cut-out frames 180 or othercomponent of the EPZ mat 112 or a combination thereof.

Still referring to FIGS. 43A-C, the exemplary connection port 278 mayreceive any desired electrical connection components (e.g. electricalconnectors 288, grounding, testing, monitoring or other equipment,wires, cables, connector pins, etc.). If desired, multiple connectionports 278 may be included at each location, such to allow flexibilityand multiple options in the position(s) and quantity of electricalconnections that can be made to the EPZ mat 112 or other desiredpurpose. In this embodiment, three connection ports 278 are shown ateach location, but other embodiments may include less (one or two) ormore (four, five, six, etc.) connection ports 278.

In some embodiments, one or more electrical connectors 288 may becoupled to one or more of the connection ports 278 of the exemplary mat112. In FIG. 43C, for example, electrical connectors 288 are shownreleasably electrically coupled to connection ports 278 on each of fouradjacent mats 112 to electrically couple the mats 112 together. Theillustrated electrical connectors 288 and connection ports 278 thusserve as the conductive interfaces 138 between the mats 112. In thisembodiment, the electrical connectors 288 include flexible, braidedsteel strips 298 and threaded bolts 296. If desired, similarly asmentioned above, the electrical connectors 288 (e.g. strips 298) may beflexible and/or coupled to one or more of the connection ports 278 withslack, such as to allow relative movement between the respective mats112 (covers 110, connected electrical components, etc.) withoutdisconnecting therefrom.

It should be noted that the corner plates 290, electrical connectionbars 270 and connection ports 278 formed in mats 112 may be used alone,or in combination with one another, or with another one or moreconductive interfaces 138 of one or more mats 112 to achieve the desiredobjective.

Preferred embodiments of the present disclosure thus offer advantagesover the prior art and are well adapted to carry out one or more of theobjects of this disclosure. However, the present invention does notrequire each of the components and acts described above and is in no waylimited to the above-described embodiments or methods of operation. Anyone or more of the above components, features and processes may beemployed in any suitable configuration without inclusion of other suchcomponents, features and processes. Moreover, the present inventionincludes additional features, capabilities, functions, methods, uses andapplications that have not been specifically addressed herein but are,or will become, apparent from the description herein, the appendeddrawings and claims.

The methods that may be described above or claimed herein and any othermethods which may fall within the scope of the appended claims can beperformed in any desired suitable order and are not necessarily limitedto any sequence described herein or as may be listed in the appendedclaims. Further, the methods of the present invention do not necessarilyrequire use of the particular embodiments shown and described herein,but are equally applicable with any other suitable structure, form andconfiguration of components.

While exemplary embodiments of the invention have been shown anddescribed, many variations, modifications and/or changes of the system,apparatus and methods of the present invention, such as in thecomponents, details of construction and operation, arrangement of partsand/or methods of use, are possible, contemplated by the patentapplicant(s), within the scope of any appended claims, and may be madeand used by one of ordinary skill in the art without departing from thespirit or teachings of the invention and scope of this disclosure andany appended claims. Thus, all matter herein set forth or shown in theaccompanying drawings should be interpreted as illustrative, and thescope of the disclosure and any appended claims should not be limited tothe embodiments described and shown herein.

The invention claimed is:
 1. Apparatus for electrically grounding aportable mat and electrically connecting the mat to at least one otherelectrically-conductive component, the mat having a top and a bottom andconfigured to be deployed on or near the surface of the earth, theapparatus comprising: a cover constructed at least partially ofelectrically-conductive material, said cover being configured to beattached to the mat sufficient to prevent said cover from separatingfrom the mat during use thereof, said cover including metallic, liquidpermeable grating configured to extend at least partially across the topof the mat and be electrically grounded to the earth; and at least oneelectrically-conductive interface configured to facilitate electricalconnection of said cover to at least one other electrically-conductivecomponent.
 2. The apparatus of claim 1 further including at least onefastener for releasably engaging said cover to the mat.
 3. The apparatusof claim 1 wherein said cover further includes an outer frame coupled toand extending around said metallic grating.
 4. The apparatus of claim 3wherein each said electrically-conductive interface is provided on saidouter frame.
 5. The apparatus of claim 3 wherein said metallic gratingis positioned at least partially within said outer frame and said outerframe is configured to sit at the perimeter of the top of the mat. 6.The apparatus of claim 3 wherein said frame includes a top, bottom andmultiple sides, further including a plurality of electrically-conductiveinterfaces, at least one said electrically-conductive interface beingdisposed proximate to each respective side of said frame.
 7. Anelectrically groundable support surface for use on or near the earth'ssurface and being electrically connectable to at least one other supportsurface, the electrically groundable support surface comprising: a lowerportion having a top and a bottom, said lower portion being configuredto be deployed on or near the surface of the earth; an at leastpartially perforated, liquid permeable cover portion constructed atleast partially of electrically-conductive material, said cover portionbeing associated with said lower portion and configured to extend atleast partially across said top of said lower portion and beelectrically grounded to the earth; and at least oneelectrically-conductive interface configured to electrically couple thesupport surface to at least one other support surface.
 8. Theelectrically groundable support surface of claim 7 further including atleast one fastener for releasably engaging said cover portion to saidlower portion.
 9. The electrically groundable support surface of claim 8wherein said cover portion has multiple sides, further including aplurality of electrically-conductive interfaces, at least one saidconductive interface disposed proximate to each respective side of saidcover portion.
 10. The electrically groundable support surface of claim8 wherein said cover portion includes an outer frame and an inner meshportion, said outer frame and said inner mesh portion being constructedat least partially of electrically-conductive material andinterconnected.
 11. The electrically groundable support surface of claim10 wherein said at least one electrically-conductive interface isprovided on said frame.
 12. The electrically groundable support surfaceof claim 11 further including multiple said electrically-conductiveinterfaces at different respective locations on said frame.
 13. Theelectrically groundable support surface of claim 8 wherein said coverportion is constructed at least partially of metallic grating havingspaces formed between metal strips.
 14. An electrically groundablesupport surface for use on or near the earth's surface, the supportsurface comprising: a mat having top and bottom surfaces, said mat beingconfigured to be deployed on or near the surface of the earth; and anelectrically-conductive cover constructed at least partially ofelectrically-conductive material, said electrically-conductive coverbeing associated with said mat and having at least one inner panelconstructed at least partially of metallic mesh having spaces formedbetween metal strips, each said inner panel being configured to extendat least partially across said top surface of said mat and beelectrically grounded to the earth.
 15. The electrically groundablesupport surface of claim 14 wherein said mat and saidelectrically-conductive cover are planar, further including at least onefastener for coupling said electrically-conductive cover to said mat.16. The electrically groundable support surface of claim 15 furtherincluding at least one electrically-conductive interface configured tofacilitate electrical connection of said electrically-conductive coverto another electrically-conductive component.
 17. The electricallygroundable support surface of claim 16 wherein saidelectrically-conductive cover has multiple sides, further including aplurality of electrically-conductive interfaces, at least one saidconductive interface being disposed proximate to each respective side ofsaid electrically-conductive cover.
 18. An electrically groundablesupport surface for use on or near the earth's surface and beingelectrically connectable to at least one other electrically-conductivecomponent, the support surface comprising: a lower portion having topand bottom surfaces, said lower portion being configured to be deployedon or near the surface of the earth; an electrically-conductive coverportion constructed at least partially of perforatedelectrically-conductive material, said cover portion extending at leastpartially across said top surface of said lower portion and beingelectrically groundable to the earth, wherein said cover portion allowsthe passage of liquid through said cover portion and into contact withsaid lower portion; and at least one electrically-conductive interfaceconfigured to facilitate electrical connection of the support surface toanother electrically-conductive component.
 19. The electricallygroundable support surface of claim 18 wherein said cover portion isconstructed at least partially of mesh material having spaces formedbetween metal strips and configured to extend at least partially acrosssaid top of said lower portion.
 20. The electrically groundable supportsurface of claim 19 further including multiple saidelectrically-conductive interfaces disposed at different respectivelocations on said cover portion.
 21. An electrically groundable,reusable, load-supporting surface adapted to be deployed on or near thesurface of the earth, the load-supporting surface comprising: aplurality of lower portions, each said lower portion having respectivetop and bottom faces; and a plurality of electrically-conductive coverportions, at least one said cover portion being associated with eachsaid respective lower portion, each said cover portion includingmetallic grating constructed at least partially ofelectrically-conductive metal strips forming openings therebetween, saidmetallic grating being configured to extend at least partially acrosssaid top face of said corresponding associated lower portion, saidrespective electrically-conductive cover portions of differentrespective said lower portions in the load-supporting surface beingconfigured to be electrically interconnected and grounded to the earthto electrically ground the load-supporting surface.
 22. The electricallygroundable, reusable, load-supporting surface of claim 21 wherein eachsaid lower portion and each said electrically-conductive cover portionis planar.
 23. The electrically groundable, reusable, load-supportingsurface of claim 22 further including at least oneelectrically-conductive interface configured to facilitate electricalconnection of said respective electrically-conductive cover portions ofdifferent respective said lower portions.
 24. A method of electricallygrounding a ground cover deployed on or near the surface of the earth inan equipotential zone to assist in preventing dangerous electricpotential differences from appearing across the body of a person locatedon the ground cover, the ground cover having a top and a bottom andbeing configured to support the weight of personnel, vehicles andequipment thereupon, the method comprising: positioning a reusable,electrically-conductive cover at least partially across the top of theground cover so that an electrically-conductive metallic grating panelof the cover extends at least partially across the top of the groundcover; the electrically-conductive cover capturing electrical current inthe equipotential zone; and electrically grounding theelectrically-conductive cover to the earth to assist in preventingdangerous electric potential differences from appearing across the bodyof a person located on the ground cover.
 25. A method of assembling andelectrically grounding a load-supporting surface configured to bedeployed on or near the surface of the earth, the method comprising:attaching an electrically-conductive cover portion at least partiallyacross the top surface of a lower portion having respective top andbottom surfaces, the cover portion including at least one perforated,liquid permeable, electrically-conductive panel having metal strips andopenings formed therebetween, the cover portion extending at leastpartially across the top surface of the lower portion and configured tosupport the weight of personnel thereupon; and electrically groundingthe load-supporting surface to the earth.